Re: [PATCH v2 7/7] iommu/arm-smmu: Support non-PCI devices with SMMUv3

["Leizhen (ThunderTown)" <thunder.leizhen-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2016/6/14 23:16, Will Deacon wrote:
> [adding ThunderTown, since he might be able to test this for us]

OK. I'm so glad to do it.

> 
> On Fri, Jun 03, 2016 at 06:15:42PM +0100, Robin Murphy wrote:
>> With the device <-> stream ID relationship suitably abstracted and
>> of_xlate() hooked up, we no longer have any PCI-specifics in play,
>> so adding support for the simpler kinds of platform device (a single
>> unique stream ID each) becomes trivial; let's do it!
>>
>> Signed-off-by: Robin Murphy <robin.murphy-5wv7dgnIgG8@public.gmane.org>
>> ---
>>
>> v2: New. Consider this one "extra bonus material" as I'm not sure there
>>     are even any suitable devices on our model to test it with (it
>>     _should_ be OK, given that I know the basic infrastructure on either
>>     side works...)
>>
>>  drivers/iommu/Kconfig       |  2 +-
>>  drivers/iommu/arm-smmu-v3.c | 36 ++++++++++++++++++++++++++++++------
>>  2 files changed, 31 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
>> index ad0860383cb3..d1c66afefeed 100644
>> --- a/drivers/iommu/Kconfig
>> +++ b/drivers/iommu/Kconfig
>> @@ -308,7 +308,7 @@ config ARM_SMMU
>>  
>>  config ARM_SMMU_V3
>>  	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support"
>> -	depends on ARM64 && PCI
>> +	depends on ARM64
>>  	select IOMMU_API
>>  	select IOMMU_IO_PGTABLE_LPAE
>>  	select GENERIC_MSI_IRQ_DOMAIN
>> diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
>> index 28dcc5ca237e..6379f0ab24fc 100644
>> --- a/drivers/iommu/arm-smmu-v3.c
>> +++ b/drivers/iommu/arm-smmu-v3.c
>> @@ -35,6 +35,8 @@
>>  #include <linux/pci.h>
>>  #include <linux/platform_device.h>
>>  
>> +#include <linux/amba/bus.h>
>> +
>>  #include "io-pgtable.h"
>>  
>>  /* MMIO registers */
>> @@ -1773,6 +1775,22 @@ static void arm_smmu_remove_device(struct device *dev)
>>  	iommu_group_remove_device(dev);
>>  }
>>  
>> +static struct iommu_group *arm_smmu_device_group(struct device *dev)
>> +{
>> +	struct iommu_group *group;
>> +
>> +	/*
>> +	 * We've currently no means of grouping non-PCI masters, so
>> +	 * there'd better not be any non-unique stream IDs in the DT...
>> +	 */
> 
> Worse: what if a SID in the DT aliases with a PCI master? It might be
> nice to have some basic snity checking, at least.
> 
> Will
> 
> .
>